Field of the Invention
The present invention relates to a test composition for detection of chloride ion in cow's milk, and a test stick for the same purpose as well as a method for manufacturing such a test stick.
In recent years, mastitis, an infection of the udder, causing production of abnormal milk, has been increasing, partially due to introduction of milking machines and this automation.
At present, about 550,000 cows among some 1,800,000 cows in Japan are treated byveterinarians for mastitis, and 10,000-20,000 cows die from mastitis.
As for the diagnosis due to the mastitis, veterinarians detect such symptoms as hardening of the udder, fever and loss of appetite, and various inspection methods have been put into practice, one of which is measurement of chloride ion in cow's milk.
The significance of measurement of chloride ion in milk is that when permeability of the mammary glands is accelerated by the mastitis, chloride ions together with bicarbonates, sulfates, sodium, ionic calcium serum albumine from the blood abnormally increases in the milk, and this acceleration of permeation which is one sign of the mastitis is detected to make the diagnosis.
As a method for detecting chloride ion in milk, the Hayden method, Sino-test No. 7 method, modified Hayden method, and Schales-Schales method have been conventionally known and have been in practice. The Hayden method is a qualitative method which determines the positivity (+) or the negativity (-), while the Schales-Schales method can analyze chloride ion in the milk with high accuracy but is disadvantageous in that the preparation of reagents and quantitative analysis are complicated, thus requiring great skill and longer time for analysis. Further this method requires special analysis apparatus and thus is considered not to be suitable for use as an outdoor clinical testing method. Therefore, development of a simplified method for measurement of chloride ion in the milk which can be performed by an inexperienced person easily in the field has been strongly sought to faciliate an earlier diagnosis.